Surgical management and outcome of lower eyelid entropion in 124 cats

Transcription

1 Veterinary Ophthalmology (2012) 15, 4, DOI: /j x Surgical management and outcome of lower eyelid entropion in 124 cats James S. White,* Rachael A. Grundon, Chloe Hardman, Anu O Reilly and Robin G. Stanley *Booval Veterinary Hospital, 12 South Station Road, Booval, Qld 4304, Australia; and Animal Eye Care, 181 Darling Road, East Malvern, Vic. 3145, Australia Address communications to: J. S. White Tel.: Fax: jamesswhitey@gmail.com Abstract Objectives To evaluate the success rate of various surgical techniques for the management of lower eyelid entropion in cats. Design Retrospective study. Animals studied One hundred and twenty-four cats with surgical correction of lower eyelid entropion of 200 eyes over a 13 year period. Methods Records of 124 cats were reviewed for signalment, type of entropion, surgical procedure performed and post-operative result. Results Combinations of the Hotz-Celsus (HC), lateral canthal closure and full thickness wedge resection techniques were used to treat 64 bilateral and 60 unilateral cases of lower lid entropion. Twenty-three cats were under a year of age, 52 cats were aged between 2 and 8 years and 49 were over 8 years old. The overall success rate for a single surgical procedure (which may consist of multiple techniques) to correct lower eyelid entropion was 96.0% per eye. The remaining 4.0% had the entropion resolved with a second surgery. A combined HC and lateral canthal closure had a 99.21% success rate of resolving lower lid entropion. Geriatric cats were the most likely age group to develop corneal sequestra; 37% of cats in this group presented with entropion and corneal sequestra concurrently. Seventeen percent of cats that presented with unilateral entropion and did not have prophylactic surgery on the fellow eye went on to develop entropion in the fellow eye. Conclusions A combined HC and lateral canthal closure was the most effective surgical technique in managing lower eyelid entropion of cats in our study. Prophylactic lateral canthal closure in the unaffected eye is recommended. Key Words: cat, entropion, eyelid, Hotz-Celsus, sequestrum, surgery INTRODUCTION Entropion refers to inversion of an eyelid margin, most typically with resultant trichiasis. 1 It is a condition that is encountered more commonly in dogs than cats. 2,3 Historically the categories of entropion have been primary and secondary. Primary entropion occurs from developmental abnormalities of the tarsus, orbit, globe, and their interrelationships. Secondary entropion can be either spastic or cicatricial. Painful ocular diseases, such as distichiasis, keratitis, ulcerative keratitis, and conjunctivitis, can cause severe blepharopasm and thereby spastic entropion. Secondary cicatricial entropion arises from acquired lid deformities from previous surgeries, injury, trauma, or chronic inflammation. 4 6 Entropion in dogs is most often associated with primary abnormalities of the tarsal plate, lid length, laxity of the lateral canthal ligament, or abnormal facial skin. 7 Feline entropion, however, often presents with a different etiology. Roberts and Weiss found in separate studies that cicatricial entropion was the most common. 2,3 However, Williams and Kim investigated 50 cats affected by entropion, finding none of the entropion cases to be of cicatricial etiology. Instead, they found the following causes: reduced orbital fat pad, previous bouts of conjunctivitis, persistent conjunctivitis, corneal ulceration, corneal sequestra formation, distichia, and finally facial characteristics associated with Persian and Maine Coone breeds that led to trichiasis and further spastic entropion. 7 Ó 2011 American College of Veterinary Ophthalmologists

2 232 white ET AL. With the definitions of secondary entropion being somewhat confusing, a new simpler categorization was suggested by Williams and Kim. 7 Two categories were proposed on the basis of age. The first category consisted of younger animals, where ocular surface irritation from keratitis, conjunctivitis, corneal ulceration, tear film instability or corneal sequestrum can cause entropion. With chronicity this could become nonreducible. The second form involved older animals. Lid laxity or tension with or without enophthalmos (presumed to be from a loss of retrobulbar tissue) would result in entropion and trichiasis. 4,7,8 Untreated entropion and trichiasis can result in numerous ocular pathologies. Some of these include, but are not limited to: conjunctivitis, keratitis, corneal ulceration, and corneal sequestra (Fig. 1). Various methods of entropion correction, such as Y-to-V correction, Hotz-Celsus (HC), lateral canthal closure, medial canthal V-plasty, and Stades method, have been described in the surgical management of entropion. 4,9 In this article we describe our results after retrospectively reviewing 124 cases of surgically managed feline entropion treated with a variety of techniques, alone or in combination. MATERIALS AND METHODS Data from 124 cats (200 surgically treated eyes) with lower lid entropion referred to an ophthalmology referral service in Australia over a 13 year period were reviewed. The following information from the patient s medical records were obtained: signalment, type of entropion, concurrent corneal pathology, surgical procedures utilized, and post-operative outcome. RESULTS The outcomes of various combinations of modified HC, lateral canthal closure and full thickness wedge resection surgeries were analysed. Cases included were from 1997 to 2010 with a minimum follow up period of 4 months. Forms of entropion included primary developmental entropion, Figure 1. Typical presentation of a cat with entropion: lower lid entropion with a secondary corneal sequestrum, surrounding oedema, neovascularisation and a mucoid discharge. entropion secondary to painful ocular conditions and late onset entropion caused by enophthalmos due to atrophy of the retrobulbar fat pad. The elected combination of techniques and exact surgical dimensions were chosen at the surgeon s discretion on a case by case basis. Surgery was performed by four surgeons (RGS, CH, AOR, RAG). The patients were divided into three groups by age: young cats less than a year old, middle aged cats between 1 and 8 years old and geriatric cats over 8 years old. The age groups were then compared in their likelihood to present with corneal sequestration in conjunction with entropion. All cats in this study were neutered. Corneal sequestra were removed at the same time as entropion surgery if required, using a superficial keratectomy. For deep sequestra, a conjunctival pedicle graft was used at the discretion of the attending surgeon. The cats were premedicated with acepromazine mg/kg (ACP2; Delvet Pty Ltd. Seven Hills, NSW, Australia), methadone 0.2 mg/kg (Methadone Ilium; Troy Labs Pty Ltd, Smithfield, NSW, Australia), and meloxicam 0.2 mg/kg (Metacam injectable; Boehringer Ingelheim Pty Ltd, North Ryde, NSW, Australia). Anesthesia was induced with Propofol 6 mg/kg (Rapinovet; Pfizer, West Ryde, NSW, Australia) and maintained with oxygen and isofluorane (Isoflo; Mallinckrodt Veterinary, Uxbridge, Middlesex, UK). One hundred and eighty-eight eyes had a HC procedure. An initial incision was made 2 mm from, but parallel to the lid margin, extending along the area of entropion plus 2 3 mm either side. A second curvilinear skin incision was made ventral to the first, usually 2 3 mm apart, but dependent on the extent of the entropion. The intervening skin was excised to a depth including the orbicularis oculi muscle. The wound was closed with 5/0 (1 metric) polygalactin 910 (Vicryl Rapide, Ethicon; Johnson and Johnson Medical Ltd, Livingston, UK) in a simple interrupted pattern, first placing a central suture, then filling in the rest of the incision with bisecting sutures. Twenty-five cats had a V-wedge excision on 34 eyes to shorten the lower eyelid as well as the HC procedure. The V excision was usually placed centrally in the lower lid for ease of surgery. The HC incisions were scored first with a scalpel then a 2 3 mm V-wedge excision was taken from the lower lid. The eyelid margin was opposed with a figure of eight suture of 5/0 Vicryl Rapide then the HC surgery was completed as before. One hundred and twenty-seven eyes of 85 cats had a permanent lateral canthal closure added to their HC procedure. Fourteen prophylactic canthoplasties were done on the contra-lateral eyelid of patients presenting with unilateral entropion. Three of these prophylactic surgeries also included a HC procedure. Once the HC procedure had been completed, the upper and lower eyelid margins were excised by tenotomy scissors for 2 3 mm along each lid and for 1 2 mm back from the margin. The lid margins were approximated in a single layer closure of simple interrupted

3 surgical management and outcome 233 sutures of 5/0 Vicryl Rapide, and then supported at the medial end by a temporary tarsorrhaphy of 4/0 Nylon (Dermalon; Tyco Healthcare Group, Norwalk, CT, USA), to be removed 2 weeks after surgery. Numerous patients had their visits photographically documented. Figures 2, 3 and 4 illustrate the typical appearance of a patient at presentation, immediate post-operative and at the 3 weeks post-operative re-check. Of the 124 cases, 64 were bilateral and 60 were unilateral. Of the unilateral cases, 31 involved the left eye only and 29 the right eye only. Thirty-nine cats (42 eyes) required a concurrent superficial keratectomy for a corneal sequestrum (Table 1). Thirty-seven percent of cats aged over 8 years old presented with concurrent sequestra, In the 1 8 year age group, 31% of cats presented with corneal sequestra and 22% of cats under 1 year of age presented with sequestra. Figure 4. The same patient as in Figs 2 and 3 photographed 3 weeks after surgery. The temporary tarsorrhaphy suture had been removed 1 week prior. Table 1. Patient age distribution and prevalence of corneal sequestra at the time of presentation for entropion surgery Age Number of cats Number of cats with sequestra <1 year years 52 (mean age = 4.2) (mean age = 11.8) Geriatric: over 8 Percentage with sequestra Table 2. Patient breed distribution and prevalence of corneal sequestra at the time of presentation for entropion surgery Figure 2. A 9 month old domestic shorthair with lower lid entropion and no significant corneal pathology at presentation. Breed Number of patients Breed percentage Unilateral sequestrum Bilateral sequestra DSH (23.6%) 4 (5.5%) DLH (37.5%) None Persian (50%) None Russian Blue (7.7%) None British None blue/shorthair Birman None Himalayan None None Ragdoll None Exotic None Burmese None None Somali None None Chinchilla X None None Figure 3. The same patient as in Fig. 2. This photograph was taken immediately after surgery. A combined Hotz-Celsus and Lateral Canthal Closure was performed and closed with 5/0 Vicryl Rapide. A 4/0 nylon temporary tarsorrhaphy suture was also placed. The most common breeds represented in this study were: Domestic Short Hairs (72), Persians (14), Russian Blues (13), Domestic Long Hairs (8) and British Blues/Shorthairs (7) (Table 2). When analyzing the number of cats of each breed with concurrent corneal sequestra, Persians were the most overrepresented at a rate of 50% (Table 2). Of the 76 (152 eyes) cats that underwent bilateral surgery, 42 (84 eyes) had a combined HC and lateral canthal closure.

4 234 white ET AL. Thirty of the 48 cats that underwent unilateral surgery also had a combined HC and lateral canthal closure. Ten cats (20 eyes) underwent a bilateral HC combined with a lower eyelid wedge resection and 11 cats underwent unilateral surgery with the same combination. Six cats had a standalone bilateral HC procedure and seven had a stand-alone unilateral HC. Two cats that presented with bilateral entropion had unilateral surgery. Both of these cats had much more severe entropion and corneal lesions in the surgically treated eyes. The nontreated eyes had minimal entropion and no corneal pathologies. Bilateral surgery was not performed due to cost constraints expressed by the owners. Neither of these cats re-presented for entropion of the fellow eye. Fourteen cats that presented with unilateral entropion had a prophylactic surgery on the contra-lateral eye (Table 3). Such surgeries were considered prophylactic as the treated eyes were unaffected, yet presumed predisposed to developing entropion in the future. Eleven of these cats were over 8 years old and the remaining three were between 1 and 8 years old. None of these prophylactically treated eyes went on to develop entropion. Forty-six cats that presented for unilateral entropion did not have a prophylactic procedure. Eight (17.39%) later developed entropion in the untreated contra-lateral eye. One of these developed entropion within 3 months of surgery. The remaining seven did so in an average time frame of 1.2 years after the initial surgery. Of those that developed entropion, four were under a year of age at the time of the initial surgery and four were between 1 and 8 years old. A second surgical procedure was required in 9 (4.5%) of the 200 eyelids that had previously had surgery, thereby making their first surgery unsuccessful (Table 4). A case was deemed successful when the patient was examined and had no clinical signs of entropion and no subsequent entropion surgery was required. The cats whose surgeries were unsuccessful were split in to two categories. The first category involved recurrence of entropion or new formation of entropion within the first 3 months post surgery. The other category was for cats affected after 3 months. The relevant eyes were then recorded within the aforementioned categories. The most common failures were recurrence of entropion after a stand alone eyelid shortening, stand-alone HC procedure or a combined HC and eyelid shortening. All the unsuccessful cases underwent a second surgery and 100% of theses had a successful outcome. The unsuccessful cases were then evaluated for which surgical technique they initially underwent. The results show that one of the 127 eyes treated with a combined HC and lateral canthal closure failed, giving an overall success rate of 99.21%. DISCUSSION In our study of 124 cats with surgically corrected lower eyelid entropion, a combination of the HC and lateral canthal closure had the highest success rate for resolving the entropion with a single surgery. Only one eye treated with a combined HC and lateral canthal closure failed. This resulted in an overall success rate for the combined technique to be 99.21%. Read and Broun found 95.2% success rate when combining a HC and lower lid shortening. 4 There appeared to be no significant difference in outcomes between surgeons. In older cats that have developed entropion secondary to enophthalmos, the HC corrects the entropion. The lateral canthal closure prevents recurrence of the entropion by Table 3. Efficacy of prophylactic surgery in cats with unilateral entropion Prophylactically treated eyes Eyes left untreated Number of eyes in age groups Eyes that needed subsequent entropion surgery <1 years 1 8 years >8 years Total <1 years 1 8 years >8 years Total Percentage of eyes requiring surgery within 3 months None None None None Percentage of eyes requiring surgery after 3 months (8.69%) 4 (8.69%) None 8 (17.39%) 2.17 (one eye) (seven eyes) Mean time before development of entropion = 1.2 years Table 4. Surgical procedures undertaken and patients requiring more surgery Procedure Number of eyes Eyes that needed a second surgery Percentage of eyes requiring a second surgery within 3 months Percentage of eyes requiring surgery after 3 months HC and LCC (one eye) None HC and WR 35 4 None (four eyes) HC alone (two eyes) 3.85 (one eye) WR alone 1 1 None 100 (one eye) LCC alone 11 0 None None HC = Hotz Celsus; LCC = Lateral canthal closure; WR = Wedge resection.

5 surgical management and outcome 235 using the upper eyelid to stabilize the lower eyelid. The lateral canthal closures will also reduce the risk of further corneal sequestration by reducing corneal exposure. The most common cause for a second surgery was the development of entropion of the contra-lateral eyelids three or more months after unilateral corrective surgery. In these instances, it took an average time of 1.2 years for entropion to develop. These cats tended to be of younger age. This suggests that there is predisposition for the cats that suffer entropion in one eye to experience it in the other. Though these cats may be predisposed, the risks of overcorrecting an anticipated problem before that problem becomes apparent may lead to other pathologies. Excessive tissue removal may lead to lagophthalmos and resultant exposure keratitis. Prophylactic HC cannot be recommended due to the risk of lagophthalmos, but a prophylactic lateral canthoplasty removes the potential for lagophthalmos, yet it still provides a stabilizing influence at the lateral lid. This seems to be important, especially in younger cats. The 14 cats that presented for unilateral entropion and had contra-lateral prophylactic surgery never went on to develop entropion in that eye. For this reason we now recommend lateral canthal closure in the unaffected fellow eye at the time of surgery for the affected eye. Roberts found that primary entropion is rare in cats, with only the Persian breed reported as having a breed predisposition. 2 The results of this study show only one of the 14 Persians involved was under a year of age at presentation and therefore the only one likely to have primary entropion. Our study did show, however, that 23 of the 124 cats seen were under a year of age, suggesting primary entropion although not common in cats is not rare either. These young cats were also the least likely of the three groups to develop corneal sequestration. Most feline entropion cases developed later in life, this is in distinct contrast to dogs where entropion is seen most commonly in young animals. 4 It can be postulated that cats are more likely to develop entropion secondary to other factors as they age. Older cats in our series were seen with entropion secondary to enophthalmos that had developed from loss of the retrobulbar fat pad. Interestingly these cats were the most likely of the three groups to develop corneal sequestration. This may reflect the severity and chronicity of the corneal irritation from the entropion-induced trichiasis. Feline corneal sequestration developed in 42 eyes in our series. This is not surprising as it has been well documented that any chronic irritation will result in feline corneal sequestration. 10 The trichiasis seen with entropion cases is a source of irritation that may predispose to the development of sequestration. Persians made up 11% of the study population. Half of the Persians in this study presented with concurrent sequestra. It has been noted that Persians, Himalayans, and Burmese are overrepresented for sequestrum formation There are a number of suggested reasons: They have shallow orbits with prominent globes, a potential for lagophthalmos and a tendency to develop medial canthal entropion. 13 In addition, brachycephalic cats have less corneal sensitivity when compared with domestic short hairs. 14 As such, the cornea is more likely to experience chronic exposure keratitis and therefore sequestra formation. In this study, we found that Persian cats were much more likely to be presented with entropion and corneal sequestration. It is felt that in these cats the sequestration was secondary to entropion as the sequestra developed in the ventro-lateral cornea. This was the area where the trichiasis was affecting the cornea. In summary, we suggest that a combined HC and lateral canthal closure is a very successful surgery to correct lower eyelid entropion in cats. A prophylactic lateral canthal closure in the contra-lateral unaffected eye may decrease the risk of entropion subsequently developing. REFERENCES 1. Bedford P. Diseases and surgery of the canine eyelid. In: Veterinary Ophthalmology, 3rd edn. (ed. Gelatt KN) Lippincott, Williams & Wilkins, Philadelphia, 1999; Roberts S, Lipton D. The eye. In: Feline Medicine and Surgery, 2nd edn. (ed. Catcott EJ) American Veterinary Publishing, Santa Barbara, 1975; Weiss C. Feline entropion. Feline Practice 1980; 10: Read R, Broun H. Entropion correction in dogs and cats using a combination Hotz-Celsus and lateral eyelid wedge resection: results in 311 eyes. Veterinary Ophthalmology 2007; 10: 1, Gelatt K. The canine eyelids. In: Veterinary Ophthalmology, 2nd edn. (ed. Gelatt KN) Lea & Febiger, Philadelphia, 1991; Barnett K, Crispin S. Feline Ophthalmology: an Atlas and Text. W.B. Saunders Co Ltd, London, 1998; Williams D, Kim J. Feline entropion: a case series of 50 affected animals ( ). Veterinary Ophthalmology 2009; 12: Moore P. Feline Corneal Disease. Clinical Techniques in Small Animal Practice, 2005; 20: Lackner P. Techniques for Surgical Correction of Adnexal Disease. Clinical Techniques in Small Animal Practice, 2001; 16(1): Hartley C. Aetiology of corneal ulcers assume FHV-1 unless proven otherwise. Journal of Feline Medicine and Surgery 2010; 12: Vawer G. Corneal mummification in colourpoint cats. The Veterinary Record 1981; 109: Morgan R. Feline corneal sequestration. A retrospective study of 42 cases. Journal of the American Animal Hospital Association 1994; 30: Glaze M, Gelatt K. Feline ophthalmology. In: Veterinary Ophthalmology, 3rd edn. (ed. Gelatt KN) Lippincott Williams & Wilkins, Philadelphia PA, 1999; Blocker T, Woerdt A. A comparison of corneal sensitivity between brachycephalic and Domestic Short-haired cats. Veterinary Ophthalmology 2001; 4: 2,